Regardless of the potential legal vulnerabilities, the marketing idea is pretty creative.
Woman Sues Toyota For Convincing Her She Was Being Stalked(CONSUMERIST.COM) It's probably a bad idea to market to consumers by tricking them with practical jokes. It's definitely a bad idea to make a consumer fear for her safety over a five day period because she thinks a stalker is coming after her. That's why a woman in Los Angeles is suing Toyota for $10 million after being on the receiving end of a Punk'd-style stunt to promote the Toyota Matrix.
Read more on Toyota's prank marketing issue.

Wow... so $10million is going to help her forget about her traumatic ordeal?? Lol!